[ Zack looks faintly annoyed at Lark's explanation, which only increases after Jon says his piece. ]

And I'm a super soldier designed to bring down armies and monsters. It's not an excuse, even if he was freaked out by what he saw.

[ And based on even that brief description, Zack has a pretty good idea which location Sephiroth chose. ]

Sephiroth told me Trevor charged him, and when Sephiroth flew up in the air, he attacked him with the razor. Sephiroth told him none of it was real, that the fight was pointless, but Trevor tried to bring him down with a rope. If was only after he was injured that Sephiroth retaliated and ended up dropping him in a well.

I don't think Sephiroth is going to actively track him down at the moment, but considering he said he was definitely going to kill him next time there was a fight between them, yeah - there's going to be a grudge.